CTT help kangaroo when accelerating help

[Pkcayenne]

Hi I had a workshop error message when I started my car this afternoon thought it was one of the vacuum pipes had split again so thought I would replace as soon as I get home well all was well until I tried to accelerate and nothing happened and I got all the gear selection PDRN lite up. So I slowed down and carried on at 60 changing gear stopped at a traffic light the. Tried to move off and the cayenne no power then lots of power and the PDRN disappeared. Was fine until I tried to accelerate and it coughed again I limped home plugged in the durametric and received the below errors.  I cleared the error took it around the block and same again from a standstill coughing. Any ideas I did change all the plugs to Bosch and one coil pack that was cracked in cylinder 4 a couple of weeks back and it has been running like a champ until today 

 

any ideas all and thanks in advance 

Edited September 3, 2016 by Pkcayenne
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[Brainz006]

I suspect you have a boost leak - - that would trigger the MAF and misfire errors. I once did not fully insert the driver side turbo-to-intercooler hose into the intercooler flange. It blew out under boost and gave similar errors including the PRND error on the dash. Check your intake tract from the MAFs to the engine for leaks. Do a pressure or smoke test for best results. Good luck.

[Pkcayenne]

HI thanks for the quick reply, why would it effect driving off from lights if I'm not under a boost condition ? Any ideas the size of pipe I'm looking for could it be a vacuum leak around the air filter box passenger side, thanks 

[Pkcayenne]

Hi can you send me a picture of this pipe or describe its locations thanks 

[Brainz006]

Yes - It's technically a boost/vacuum leak issue so it can affect drive ability at all speeds depending on how bad the leak is. It's caused by unmetered air from a leak between the MAFs (mass air flow sensors, which are just below the air boxes) and the engine. And when the MAF readings don't match what's actually entering the engine, then the fuel mix will be off (causing the engine to run rough and throw codes). You need to check all the intake plumbing for leaks, cracks or things that came disconnected. From your description, it sounds like you have a big leak (because you have trouble at higher speeds too), so start with the throttle body and examine all the charge piping (Y-pipe, pipes to ICs, hoses from ICs to turbos, turbos to MAFs). Most of that piping is ~2.5" black plastic or rubber. Note also that there are some small hoses on the underside of the Y pipe that can come loose or get damaged by the water pump pulley that aren't obvious without pulling off the Y-pipe, and can cause issues. It's also possible you have a leak on one of the vacuum hoses or corrugated plastic tubes attached to the intake manifold. Inspect those too, but it can be harder to visually troubleshoot those hoses as they are smaller and many of them are obscured by other parts. That's why a pressure or smoke test would be most useful. Lots of videos on YouTube on how to do this (generically). Hope that helps. Good luck.

[Pkcayenne]

Thanks will check one of the pipes going to the maf hasn't fallen off as this was loose when I cleaned the maf some weeks back also will check the y which I read can be split. Smoke test will have to research how to poor mans way weird that I've had the usual workshop error and cracked 1/4 inch rubber pipes near the coolant reservoir.  As you said the black pipes over the infectious will be hard to check. Thanks again on this labor days weekend 

[Brainz006]

And make sure the MAFs are plugged in. A loose connection could also do it. Good luck.

[lewisweller]

On 3 September 2016 at 6:37 PM, Pkcayenne said:

Thanks will check one of the pipes going to the maf hasn't fallen off as this was loose when I cleaned the maf some weeks back also will check the y which I read can be split. Smoke test will have to research how to poor mans way weird that I've had the usual workshop error and cracked 1/4 inch rubber pipes near the coolant reservoir.  As you said the black pipes over the infectious will be hard to check. Thanks again on this labor days weekend 

Home made smoker can be made from a clear 2 litre bottle, drill the cap a hole slightly smaller than a cigarette butt, also make a hole in the side of the bottle to fit an air source hose/ gun/ pipe from a air compressor or hand pump etc. 

Before testing Remove the air box pipes both sides and cover with a plastic food bag and duct tape tightly to make pipe ends leak tight. 

Remove the intake Y pipe mounted Map sensor, (pictured above my thumb in the second image) one torx screw T25 I think or a flat blade will do it, using the Map sensor hole place the bottle with a lit cigarette in the cap, put bottle upside down on the map sensor empty hole in the intake. 

Pressurised the bottle with air to force the cigarette to burn and push the smoke into the intake Y pipe and around the system. 

 

Look for smoke escaping around left and right side piping from turbo to intercooler and all those pesky vac tubes and other small pipes. 

You may need to used more than 1 cigarette to fill with smoke, I used 3 Total to get smoke everywhere it wanted to go, didn't find a leak though. 

 

[Pkcayenne]

Thanks I just tried some seafoam it runs even worst now, the thing I found today from cold runs cayenne great as soon as it gets hot looses all power from the lights. Filled the car with premium fuels......does this kind of point to a coil pack issue even though no errors ?

[Brainz006]

Seafoam in the intake or gas tank? Use Techron if you are worried about deposits - it does smooth running but won't fix the issues of the magnitude you're having. Did you check that the MAFs were plugged in and search for obvious boost leaks? Have you pulled the codes again to confirm the same ones? The codes you have could be coils, but most people complain of rough idle with coils, and from your description you seem to have rough acceleration. Since you've already fixed one cracked coil (and replaced the plugs) the next step would be to recheck the other coils for obvious cracks and move the #1 and #8 coils to different cylinders and see if the error codes move. And you might consider replacing all the old coils proactively depending on how much you value your time/money. Also double check that your coils are fully plugged in. I seem to recall the connectors being hard to seat fully. One other thought, if it idles fine, but has no power/won't accelerate, maybe there is a fuel pump issue (seems like that would throw more codes, though). I've not had fuel pump issues (knock wood) but its reasonably common on the forums . Search for "Cayenne fuel pump test" as there are two pumps, and pulling a fuse can diagnose their functioning. Good luck.

[Pkcayenne]

Thanks beginning now checking the coils still no codes appreciate your Ponters